Sudan Black B
|Sudan Black B|
|Jmol-3D images||Image 1|
|Molar mass||456.54 g/mol|
|Melting point||120–124 °C|
| (what is: / ?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Sudan Black B (C29H24N6) is a nonfluorescent, relatively thermostable lysochrome (fat-soluble dye) diazo dye used for staining of neutral triglycerides and lipids on frozen sections and some lipoproteins on paraffin sections. It has the appearance of a dark brown to black powder with maximum absorption at 596-605 nm and melting point 120–124 °C. It stains blue-black.
Sudan Black B can be used to stain some other materials than the other Sudan dyes, as it is not so specific to lipids.
A use of Sudan Black B is in fingerprint enhancement. It is useful for detecting fats that are contaminated with oil and grease.
Production and composition
Sudan Black is formed by coupling of diazotized 4-phenylazonaphthalenamine-1 with 2,3-dihydro-2,2-dimethyl-1H-perimidine. Therefore the main product expected was 2,3-dihydro-2,2dimethyl-6-[(4-phenylazo-1-naphthalenyl)-azo]-1H-perimidine. However the dye resulting from the above reaction product actually contains many, up to 42 colored and colorless by products that can be fractionated. The two major products were blue in color confirmed by various chromato-graphic (TLC and column etc.) separation and spectroscopic (IR, NMR, Mass) identification were named SSB-I & SSB-II (Rf values of 0.49 and 0.19 in thin Layer Chromatography). The above described product indeed turned out to be SSB-II which comprises up to 60% of the mixture, and the SSB-I was 2,3-dihydro-2,2dimethyl-4-[(4-phenylazo-1-naphthalenyl)-azo]-1H-perimidine.
Is there an "Acetylated" Sudan Black?
Although there are abundant applications of a Sudan black derivative named acetylated Sudan black, chemical analysis shows that thare is no addition acetylation but rather a loss of some of the components of the mixture.
- "Histochemistry. 1977 Dec 7;54(3):237-50. Sudan Black B: chemical structure and histochemistry of the blue main components. Pfüller U, Franz H, Preiss A". Springerlink.com. Retrieved 2012-05-25.
- HISTOCHEMISTRY AND CELL BIOLOGY Volume 16, Number 1 (1968), 68-84, DOI: 10.1007/BF00306212 Thin layer chrornatography and histochemistry of Sudan Black B A. G. W. Lansink
- "Histochemistry. 1989;93(2):213-6. Evidence against the existence of acetylated Sudan Black B. Lauder RM, Beynon AD". Springerlink.com. Retrieved 2012-05-25.
- Stains File entry